Just an FYI.....rock salt and aquarium salt are both sodium chloride....so save your money and just get the rock salt....you can use that if you need to treat the fish for anything......

What you want to avoid in sodium chloride is the anti-caking ingredients-long term use of this can make the fish toxic....Iodine is not an issue in the amount that is added-plus it is a different form (Iodide) anyway and you are most likely adding some of it to the tank as a common ingredient in some fish food, plant food and other misc things we use-then on top of that Iodide can sometimes be beneficial in small amounts......so the myth about salt with Iodine....is just that.... a Myth......

One thing you might need to add to the list is Epsom salt(Magnesium Sulfate)-this is good to have on hand in general and plastic veggie wrap to go over the top of the tank-this is important to help retain heat/humidity over the water for when the fry start to develop their labyrinth organ at about 2 weeks.
What about an eye dropper....I love these to target feed BBS and for other things as well and if you don't already have one a Brine shrimp net-these are great to use to harvest the BBS. I am sure you already have an air pump for the BBS hatchery-I would also get a "T" valve so you can split the tubing for the air pump to keep 2 hatcheries going 24h apart-Its best to feed newly hatched BBS with their yolk sac intact for best nutrition-really important for the first 2-3 weeks-especially if BBS is the main source of nutrition. Once the BBS absorb their yolk sac and the fry are over 2 weeks-I will feed the older/larger BBS after I supplement them in HUFA product called "Silcon".....when fry are deficient in HUFA you can have mass, sudden deaths-usually they will twirl to the bottom then die.